Helmet shields are what I do. Dampen the leather while cutting with the swivel knife, it makes carving go smoother and ensures your depth. When stamping, have your leather on a thick stone surface. I have a 1.5 inch piece of granite counter remnant thats about 10x10". having a good work bench standing on concrete or hardwood floor makes a difference in transferring your energy from the mallet. Getting smooth beveling does take a lot of practice, but starts with good leather, as well as properly casing the leather. Think of it like needing to get the leather wet to the depth you want the stamp or bevel to be. I thoroughly wet the face of the leather, then let it almost dry. I use a piece of plastic wrap to keep the moisture content of the rest of the leather until I'm ready to start embossing that section. I have a 12 oz mallet and a 2.5 lb deadblow mallet. I prefer the deadblow mallet, I can choke up or down as needed to provide the force I want. Tap a lot while slowly moving the beveler. I'd say you should have tapped the tool three times once you have moved it the width of the bevel face. If you want your impressions to be deeper, try a heavier mallet or maul, rather than striking harder with a lighter mallet. I've found that leads to staggered impressions. If you have some uneven marks despite your best efforts, go back with the beveler by hand, tilt it to the left or right, apply firm pressure, and rub it over the uneven spots, kind of like burnishing. That can smooth out some lines and make the impression cleaner looking. Most of all, take your time, and don't do too much at once. Getting fatigued or frustrated can really set you back, and its easy to do once you are starting out. If you need help or have questions specifically pertaining to helmet shields drop me a message, I'm happy to help.
